1. Field of the Invention
The invention concerns a hinge arrangement for a hinged part that can be held in either a first or a second position by an energy storage device which is attached to a stationary bearing.
2. Description of the Related Art
French patent No. 1,467,870 teaches a two-link over-center hinge mechanism which must be placed on the side of a hinged part towards which the hinged part will swing. This is undesirable if this means the hinge must be placed on the outside surface of the hinged part, e.g., on the outside of a container with a hinged top.
Great Britain patent Specification No. 654,766 teaches a two-link over-center hinge mechanism which is placed entirely in front of the pivot point for a hinged part, thereby consuming otherwise usable space. In addition, the hinge structure requires a plate attached to a surface, e.g., a cupboard shelf, adjacent to the hinged part, and thus cannot be used if there is no such adjacent surface.
The over-center hinge arrangement of European patent No. 0 007 104 relies on a torsion bar spring, one end of which is pivoted from a stationary bearing while the other end is pivoted from the hinged part. The torsion bar is most highly deflected, and hence most highly stressed, when the hinged part is in a position intermediate to the end positions. As soon as the hinged part moves past this dead center position, the energy storage device will push the hinged part to one of the end positions. This hinge arrangement has the disadvantage that its energy storage device must be specially formed, which results in an unfavorable cost situation.